The present invention relates to a seating unit having an adjustable back tension function and an adjustable back stop function.
Comfort, simplicity, and adjustability continue to be highly-demanded features in seating. Specifically, it is desirable to provide a control that is easy to operate, simple to manufacture and assemble, has relatively low cost and relatively few components, and that has a modern thin sleek appearance. It is further desirable that the structure complement the ability to provide weight-activated support upon recline so that heavier seated users feel secure upon recline even without adjustment. In regard to adjustability, it is desirable to provide controls that are easy and intuitive to operate. For example, many chairs having a reclineable back also have an adjustable spring for varying the back support provided upon recline, but most controls work against the spring to compress the spring during adjustment. This takes considerable effort, even if a mechanical advantage is provided, since the springs are substantial and there is significant energy input required to compress the spring. Even adjustments that decompress the spring require effort to overcome frictional forces that prevent unexpected decompression. Further, seated users constantly find themselves searching among several different controls trying to find the correct control for the particular adjustment that they desire. Still further, once the proper control is selected, the user still has to figure out which way to adjust the control to achieve the desired effect. It is desirable to invent a more integrated control mechanism that provides a logical and intuitive combination of chair adjustments, where increasingly supportive adjustments cause an increasing level of back support, even though the increasing support is provided by different mechanisms.
In addition to the above, it is desirable to provide a chair that is optimally designed to use recyclable parts, and that uses components that can be easily separated for recycling and/or repair. Expanded thermoset foam products are usually classified as not recyclable, and further they are generally considered to be unfriendly to the environment as compared to steel, remeltable thermoplastic, and more natural materials. Eliminating thermoset foam would be a significant step toward making a chair 100% recyclable. However, the comfort and cost advantage must be maintained for competitive reasons.
Accordingly, an apparatus solving the aforementioned problems and having the aforementioned advantages is desired.